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Page 2 Outline In the case of crucial experiments: What should the PDG show? A) Result of experimental group ignoring later corrections or B) Reanalysis incorporating best estimates (with appropriate errors) of those corrections Clearly I believe that B) is the correct answer BUT let me explain the case of NuTeV and then we can have a discussion...

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Page 22 An additional source of CSV In addition to the u-d mass difference, MRST ( Eur Phys J C39 (2005) 155 ) and Glück et al ( PRL 95 (2005) ) suggested that “QED splitting”: which is obviously larger for u than d quarks, would be an additional source of CSV. Assume zero at some low scale and then evolve − so CSV from this source grows with Q 2 Effect on NuTeV is exactly as for regular CSV and magnitude but grows logarithmically with Q 2 For NuTeV it gives: to which we assign 100% error

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Page 27 Correction to Paschos-Wolfenstein from ρ p - ρ n Excess of neutrons means d-quarks feel more repulsion than u-quarks Hence shift of momentum from all u to all d in the nucleus! Negative change in ΔR PW and hence sin 2 θ W ↑ Isovector force controlled by ρ p – ρ n and symmetry energy of nuclear matter − both well known! N.B. ρ 0 mean field included in QHD and QMC and earlier work but no-one thought of this!!

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Page 30 Separate Neutrino and Anti-Neutrino Ratios Biggest criticism of this explanation was that NuTeV actually measured and, separately: Claim we should compare directly with these. Have done this: Then moves from c.f. in the Standard Model to ; moves from to, c.f. in SM This is a tremendous improvement : χ 2 changes from 7.2 to 2.6 for the two ratios! Bentz et al., Phys Lett B693 (2010) 462 ( arXiv: )

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Page 31 Summary There are 3 well identified and unavoidable corrections to the NuTeV result I. CSV: a) m d ≠ m u : known and calculated a decade before NuTeV − If not ignored would have reduced “anomaly” to ~2σ 2003: ~ model independent result for relevant moment 2011: Finally lattice results for δu + and δd + in excellent agreement with phenomenology